But there's a problem with Wozzilroy, and it's not that they're too cute.

After soaring to the top of their respective sports at young ages, each has fallen on hard times recently, and some people think the struggles are related to their relationship.

With the British Open this week, McIlroy's poor play has been placed firmly under the media microscope. Not only has McIlroy not won a tournament this year, he missed the cut at his last two tournaments in Europe. To make matters worse, ever since signing a humongous deal with Nike, McIlroy has had issues with his new clubs. But Johnny Miller, an NBC golf analyst, thinks McIlroy's problems extend beyond his bag.

Tony Manfred of Business Insider compiled McIlroy's results from the "Wozzilroy" era, and this chart speaks for itself.

At least McIlroy has company in his misery. As Manfred points out, Wozniacki won three tournaments in the five months before she started dating McIlroy in the summer of 2011. Since then, she's won a total of three tournaments. Wozniacki has bombed in her last two Grand Slam tournaments, losing in the second round in both the French Open and Wimbledon.

While love is truly a potent force, it's important to note that there are other factors contributing to Wozzilroy's struggles. McIlroy has had some issues with his swing this year, and Wozniacki has been plagued by an ankle injury.

"I think what Rory and I have is very special," Wozniacki said last month. "He's trying to work it out with his schedule, I'm trying to go and see him when I can, so in that way it's been working out well so far. We speak every day but we never have a set time where we have to speak. We just do it because we want to."

So, struggles aside, if they're both happy, isn't that all that matters?